Briquetting machine



May 24, 1932.

E." L]. BYERLEIN ET AL 1,860,075

BRIQUETTING MACHINE Filed March 1," 1930 4 Sheets-Sheet 1 INVENTORS ATTORNEYS May 24, 1932'.

E. J BYERLEIN ET AL BRIQUETTING MACHINE FiledMarch 1. 1950 4 Sheets-Sheet 2 5L4 IN VEN TORS ATTORNEYS May24, 1932. E. J. BYERLEIN ET AL Y'BRIQUETTING MACHINE 4 Sheets-Sheet 5 Filed March 1, 1930 INVENTORS ATTORNEYS May 24, 1932. E.J. BYERLEINY ET AL BRIQUETTING MACHINE Filed March 1, 1950 4 Shets-Shet 4 ATTORNEYS,

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Patented May 24, 1932 r 'IUNI'IIEDF' STATES ERLE J. BYEBLEIN AND FRED GRAFQJR, on .wnuwnirosa fwiseoivsnv, AssIeNonsJro 1 MILWAUKEE FOUNDRY EQUIPMENT 00.,

TION OF WISCONSIN l Application filed March 1,

Thisinvention relates to improvements in briq'uetting machines, more particularly, al-' though not solely, adapted for compressing p videa briquetting machine. which isyof simmetal borings and cuttings into briquettes. It is one of the objects'of the present invention to provide abriquettin'g machine which is adapted to exert considerable pressure upon batches of loose material to form'briquettes therefrom of such solidity or density as-to provide briquettes which will hold their shape, and in the case of metal, permit the easy handling and 'meltingthereof; 1

A further object of theinvention is to provide a briquetting machine which W111 apply a comparatively lig t pressure with consid erable movement to initially separate a batch of material from the-supply mass. and then automatically increase the pressure on the briquette under formation to the predetermined degree to ation. i H r A furtherobject of the invention is to provide a briquetting machine in whichthe briquette after formation is held in position while a portion of the forming means is stripped from thebriquette preparatoryto discharging the completed briquette from the machine. If

A. further object of the invention is to provide a briquetting'machine 'inwhich a compound piston and cylinder construction is used having novel. means controlling 'the rapid feed. of the fluid medium to the'large cylinder while the smaller piston is under pressure and'initially compressing the material preparatory to the final augmented pres- N sure used in completing the briquette. H

A further Object of the invention is to'proe vide a briquetting machine which will always compress the material forming them; quette to a predetermlneddensity regardless of the amount of material being formed into a briquette.

A further object of the invention to provide a briquetting machine'havingTelectrical complete the forming operrial holder and die in Ls-ition;

on MrLWAUKnn'wIsoousm; A CORPORA- BRIQUET ING MAcHINE.

1930. Serial No; 432.395.

means for automatically controlling the 8011 tinuous operation of theiparts.

A further object of the-inventionis to prople construction, is strong and durable andis .well adapted for thepurpose described. r 7

With theabo've and other objectsin view, the invention consists ofthe improved bri-v the same reference characters same'partsin all of the views: I N Fig. 118 a centrallongitudinal sectional view of the improved briquetting machine; Fig. 2 is a central horizontal-sectional View taken on li'ne2-2 of Fig. l; j

.Fig. .3 is a transverse sectional view'taken Y on line 3-.-3 of Fig. 1; V 7 Fig. 4 is a similar view-taken on line 4+4 of Fig. 1;

Fig. 5 is a horizontal sectional detail View showing the,piston.plunger' in its forward batch compressing position; i

t Fig. 6 's a'similar view showing the matebriquette stripping po- Fig; 7 r is avertical sectional detail view Fig.6;-

- Fig. 8 is a detail side View of a portion of i r the machine showingoneof the electric con- 7 trolling .devices j a j 3 Fig. 9 is sectional detail view of the wear plate; and j Fig-'10 is a'diagrammatic' view oi the com plete briquetting machine and its controls, a portion of the machine proper being shown in section. a

Referringto the drawingsand more par- 1 I ticularly to the, dia-grammatio .view shown in Fig. 9', the reference lnume ralv 12 indicates V the briquetting machine proper, 13 the power 1, pump, lathe pressure fluid storage tank ,15

showing the partsin the sameposition as i p I the fixed frame member 27,ag'ainst which the an electrically operatedsolenoid controlling valve,16 a four-way controlling valve; 17 a three-way controlling valve, 18 and 19 resistance valves, and 20 and 21 automatic pressure foot valves. The parts thus briefly mentioned are all connected together and form part of the complete structure and later will be more specifically described.

Now referring to the briquettingmachine proper the numeral 22 indicates channeled frame members upon which are mounted compressor cylindersz23 and '24'and stripper cylinders and stripper return cylinders 26.

V V Thesecondary compressor cylinder' 24 which is of comparativelylarge si'zeis spaced from briquettes are compressed; bybrace bars 28. Said brace bars take the compressor strain and are therefore equi-distantly; spaced around the compressorcylinder 24. A removable wear plate 29 mounted on the fixed frame member 27 takes the direct wear ofthe compression and can be easily replaced when worn. The stripper cylinders 25' are carried by the fixed frame members 27 and said cylinders have pistons 30 which are connected to and form part of the pistons 31. Said pistons 31 extend into the alined stripper return cylinders 26 mounted on the forward end of the compressor cylinders 24. Medial portions 32 of the pistons 30-31are reduced in diameter to have a hopper 33 clamped thereto." A die member 34 having a circular bore 35 extending therethrough in axial alin-ement with the wearplate 29 is mounted in the outer end portionof' the hopper 33. A drop door 36 is hinged to the lower side portion of the hopper 33 to permit cleaning said hopper.

The large secondary compressor cylinder.

24 is provided with apiston 37 formed with an integral piston rod 38 which extends through. the forward end of the cylinder. A cylindrical plunger or die ram .39 bolted to the forward end of the piston rod 38 extends reciprocally into the hopper 33 in axial alinement with. the bore 35 of the die member 34 which it snugly fits.

' The primary cylinder 23 is of comparatively small diameter and-its piston 40 is provided with a piston r0d41'which reciprocally extends through the rear end of the secon dary cylinder 24 and is bolted rigidly to the secondary piston 37 and always reciprocates therewith. As thus arranged the primary piston initially moved the plunger" 39 the greater portion of its movement andpower is then applied to the secondary pistonto complete the stroke with sufiicient pressure to complete the compression of the briquettes.

To permit the comparatively quick movement of the primary piston, it is necessary to prov de means for quickly feeding thexpower medium, such asoil, to the'secondary cylinder, and to accomplish this result the oil storage tank 14 is positioned above andis charge intothetank.

mounted directly on the secondary cylinder 24. A valve casing 42 mounted on the said secondary cylinder 24 extends upwardly into the tank 14 and is formed with a large bore 43 opening into the secondary cylinder 24 to the rear of its piston 37 Transverse openings 44 open communication between the storage tank 14 and the bore 43 so that the oil can freely and quickly flow from the tank to the secondary cylinder while the oil under ressure isforcin 'the Jrimar 4 is-ton'4Orfor- 'The said. valve when in its lower position closes the port openings 44 leading to the secondary cylinder 24. The valve stem 46 is formed with a small drive piston '49 and a valve recess 50 for controlling the flow-of the oil under pressure to the secondary cylinder. A pipe 51 connected tothe rear end of the primary cylinder 23 extends upwardlythere from and into the storage tank 14 and is also connect-edto the, valve casing port-511% a point a short distance above the bore43 and below the'valve recess 50 when the valve is in its upper position as shown Fig. 1.- 1 A branch pipe 52.provided with a relief valve. 53

is connected to the valve casing 42 above. the

small valve piston 49 to move said valve piston downwardly when thejpressure in the branch pipe. increasesto a predetermined extent to'overcome the tension .of thevalve a.

spring 54.' When. the valve 45 is moved downwardly the port 0penings144 will be closed and the'recess valve portion '50will open communication between the duct. 51 and thebore 43 and permit the oil to flow into said bore and through the bore 55 of the valve :45 and then into the secondary cylinder to move the secondary piston to complete the crushing stroke of the plunger 39.

In case the plunger would be checked in its movement 'the pump would build up and increase the pressure on the oil andthe in creased pressure would open'the relief valve 53 andrelieve'the pressure and prevent dam age to, parts; The reliefvalve maybe located at any desirable point in the line to dis- The oil under pressure is controlled bvthe piston valves wlthin valve casings 15, 16 and 17 before mentioned, which maybe of any ordinary construction and operated in any manner desired. In the form shown the master valve 15 is moved by anelectric solenoid 56 in one direction against the tension of a coiled spring 57. Current to, the solenoidis supplied from a sourceof electrical supply an d the Wires 58"le'a'dto switch 59 mounted on one of the return strippercylinders: ,An arm strip the briquette from the die-,'iand breaks the circuitto the solenoid when the hopper moves forwardly to "briquette forming posi- 60 mounted on and moving with the hopper I member operates the switch to complete-the circuit When-the hopper moves rearwardlyto When the solenoid is Y ie-energized shown the oil under pressure from the pump 3 13 will be'forced through the pipe 51150 the ports 62 and 63 andthence through the vpipe 64.- to the'port's 65 and 66 0f the valve :16; From the port-66 the oil WlllfflOW through the pipe 51 to the'primary'cylinder 23 and.

force the piston thereof forwardly. to initially compress the material: l/Vhile the. primary.

piston is being moved forwardlyflm oil from the tank is free. to flow frornuthe tank 19;

through the ducts 44 and43 and the valve 45 and into the secondary cylinder 24 to-permit t'herapid movement of the; piston 37 thereof.

The resistance of-the-inaterial hei ng com pressed 'Wlll cause the pump to buildup in- V creasing pressure 01111110011 wlth the-result that 'ata predeterminedpressure, the spring pressed valve. 54 of the valve casing 19 will open andpermit tllHOllrtO flow through the branch pipe 52 to the cylinder 67 of the slide valve 17 and move the pistons?) thereof to the right or-doivnvvardly; :This movement will slide. the .valves'45' and50. to close the flow of oil through the ports 44- and openthe flow through the ducts 5.1T and 43"to the secondary. cylinder 2 l. The pressure of the, pump willnow be also directed againstfthe secondary piston, and due to its larger diameter-will causethe plunger to'exert apthe partlycompressed material to further compress it into asolid brique'tte which in the case of motal cuttings wilhform an rintegral'mass.

The briquettes will vary in length due to the fact that'the stroke of the plunger is controlled by pressure, and further th'atathe amount of material forced fro'm'the hopper into the die may vary, but in jall cases the -1naterialwill be subjectedto substantiallythe same pressure. 1 i

When the briquette has beenncompresscdj to thepredetermined extent the resistance of the material to further imovement of the plunger Wlll causethe pump to build nnthe sistance valve 18. and p-ermit'the oil to flow through the branch pipe4i3' to the small inder 68 of the valvecasinglti and more the valve piston 69 thereof to the left. This? movement will cause the piston valve 7.0

close the port 66 and'the duct 51 the pis ton valve 71 to open communication betweenthe ports 65 and 7 2. VA branchduct 64E havthe pressure inthexduct 43exceeds the .pres sure inthe duct6 l.

secondary cylinders Willbe cut off and said With thefvalv esf'in this? position thepres-sure to the primary and parts will remain stationary; .This wil'l'p'er mit the fluid under pressureto flow from the pump throughthe solenoid valve 15; duct 64:;

valve 16 and ports 65 and 721 to ducts j73 ex"- tending and connected to the stripper'ciyh inders'25. A- checkvalved duct 73 extends from the duct 43to the ducti7-3- to equalize" the pressure on the outer sides of the. valves and 71 When said valves are. at'iest: i The pressure exerted upon thestripper pistons- 30 ofthe pistons, the die 34 Will lee-stripped from the loriquette'ii just formed; It is t o be understood that "Whllfi "the stripping 'o'peration is taking place the plunger; asgb'efore mentioned, remains in' its forwardposition and holds the hriquette against fthe Wear will forcesaid pistons rearward-1y and asuie- A hopper 33 anddie 34 are carried by portions .785 3 hopper 33 through the intermediary of th ef switch arm 60 and 'switch' 59 completesijthe coil thereof to draw the'solenoid core'e56 to '90 plate 29. The rearward movement 'offithecircuit' to the solenoid" 56 and energizes the the left againstthe tensi'on ofthe. retrieving spring 57 The pistonvalves 75and 76 con nected to said core 56Will he movedtoj the left and disconnect the pressure fluid from cylinder 24' to move the pist'on rearwardly to the left. Thismovement Will force -the the-duct 64-and connectitto the d HCillj,77 p 1 leading to the front 'port-ion of 'theprimary Plunger 39 e r a d- W0 release theta quette 74 hichwill drop intoithe-receptacle 'm A positioned below the machine. A yielding ,plunger 29.mounted' in the Wear plate 29 and normally projecting outwardly a-slight v distance serves'to preventlthebriquett'e from sticking to the Wear platem hen the plunge .er is pressed inwardly during the formation 3 v of a briquette, the innerportions offthefplung.

er will rest against shoulder -29. While the r outer face of the plunger is flush with out-er face of the Wearplate; I J' r Almost simultaneously. with th'elast men tioned mOvem'entsthe mediu'm un defipres rear p'ortions of the'stripper return cylinders 26 and force" the 'stripper return pistons 31 u -forWardly'-and; the hopper 33110 "its normalf pressure on the 011 sufficient to open the r,e-'

the branch pipe 78 prevent direct returnof the fluid medium to the. duct 77 :but' permit Q it toreturn to said pipethrough the primary cylinder;

l I Vhen the primary piston reaches the end V ofltsflstroke the pressure-medium can thenflow through the primary-cylinder upwardly through the duct 78 tothe pipe 78 and tothe 1'80 which has'flowed into thedifferent cylinders v will be discharged therefrom through the While the medium under pressure is flow- V ingzthroughduct'f? .itwill'also flow through abranch duct-'SO leading to'thecylinder Gland assistthe spring'? to force the piston 49 to the left ("Fig 10-) imposition to repeat the cycle :of'operations." At, the same time the pressure onithe fluid medium will build 'up to overcome the :pressure of the foot valve 20 and-:th'e fluid will pass throughthe duct "81 into the piston :valve cylinder 82 and vaetuate the piston '83 thereofto move the pis- 'TtOIl 'valves '70 and 71 to the right to their initial "positions'as shown in Fig. 10.

retui'niduct '84 extending from the valve I casing'lfi to the storage tank ltgis intersected -by :the ;automatic pressure foot valve'21to permit the return ofthe fluid to the tank whenythepressure is sufli cient to overcome :the resistances-of the valve. The end of the duct connected to the valve casing 16 is in communicationwithzthe valve duct 85 which :connectslthe:oppositeen-ds'of the bore of the ival-ve casingtogether to permit the fluid medium to surge =back and forth "as the piston "valve is reciprocatedtherein.

I The numeral 86 indicates thereturn pipes Aeduct 87 connecting the outer end portions of-the'bore of the valve casing '15 isconnected to the storage tank l l'by a pipe 88 to permit excessfifluid medium to returnlto --theitank. a V

' lit is to be understoodthat the fluid medium same ducts. V r a V V While the invention has --been described :as :.a :brique-ttingmachine, itsis to be under- ;stoodthat the invention contemplates the iInQthOd of making briquettes in which the :briquettes are .all compressed to substantially theisameuextent regardless of the amount of material in each briquette.

)Fromthe foregoing description it will be c .seen'ithat' it is onlynecessary to supply the hopper with metal cuttings or other material I i -and the machine will continue to form the briquettes fromithe scrap material quickly and economically. *It will also be seen that .in formingbriquettes of scrap metal cuttings, l-thatthe'briquettesWill be compressed to such an-extent as to have the appearance of being solid blocks of metal, and which blocks or briquettes-may .be easily melted for further 'i'use. It will be further seen' that the opera- I {:tion-of forming the briquettes is very simple :dervhaving a pistonvfor'moving the plunger 5 ,torforee materialfrom'the hopper'intothe die .ing the plunger with greater-pressure for completing the compression otthe material,

pressing of the material, :means :for supplyextendingfromthe storage tank to the pump.

-er to its initial position to lrelease'rthe 'brimaintaining the plun ger in briquetterholding and is Well adapted for-the purpose described.

mea ows and :to zinitially :compress material to a predetermined extent, :a secondary cylinder :ofxlarger diameter -l1auinga piston :for -movmeans .ior; supplying fluid under pressure to the primary cylinder andpfluid Lfreely to'the secondary cylinder zduring 'the :initi-al .com-

ing fluid under pressure to the s'econda'ryzcyh .inderafter the iinltial compression, and me'ans for :stripping the ndlfi iirom the -:eompleted .briquette -while the plunger remains :in :its compressingposition;

2. A briquettlngimachine,'.eomprising.a die 'm'emberpa hopper ifor holding loose material adjacent thereto, a plunger, a primary cyl nder having .a piston formovmgthegplunger to force material -from the hopper into the die and to initially icompress 1said material to "a 105 predetermined extent, a .isecondary cylinder oflarger diameterhavin'gzapiston for'mov; ing the plunger with greater pressure for completing the :;compression 20f :thermaterial,

means ifor supplying fluid under pressure "to r the primary cylinder and :fluid freely to the secondary cylinder during :the initial zoompressing ofithe zmaterial,imeansjfori supplying fiuid'undernpressure toitheisecondary cylinder aftertheinitial compression; means for strip- $85 ping the diefromr the i'comp'leted cbriquette While the plunger is holding the :completed briquette, and means forrreturning the plunge quette, no I i V H 7. H00

3. A briquettingimachine;comprising adie member,ia hopperi'itor holdingloose material adj a'centthereto, 2a plunger, aprimary oylin derhavinga jpiston forinrovin'githe 'plungerito 7 force material from the hopperiintoth'erdie 1 o and to initially'c'ompress rsalid material to a predetermined extent, Fa 'se'eondary "cylinder of larger diameter having a piston for mov- --ing the plunger "with "greater pressure for completing the compression of thermaterial, 3110 means forisupplying fluid under pressur'e to the primary 'cylindernnd fluid ifreely to th'e secondary cylinder during :the initial =fcompressing of the material,'r-means forsupply' ing fluid under pressure to the "secondary H5 cylinder after theinitial rcompressionjmeans V controlled by the resistance ofethe nraterialto be 'compressedifor stopping theisupply of pressure fluid to the secondary cylinder vvhile I20 position and strippingthedie from'theibriquette, and means for returning the plunger to its initial positionto release thesbriquette.

- 4. A briquettingrmachine, comprising a 1 frame, a 'hopper for holding loose material, 3125 a die member adjacent the hopper,a:plunger extending into the hopper'i'n 'alinementwith the die, a primary cylinder'h-avinga piston for moving the plunger to force "material from the hopper :into the die'and againstaa 3-330 material, a pump and'a fluid holding-{tank positioned. to supply fluid under pressure {to the primary cylinder and at the same time,

permit fluid to quickly and freely flow, from the tank to the secondary cylinder during the initial compressingof the material, a valve controlled by the resistance of the mater1al being compressed for directing-fluid under pressure to the secondary cylinder'to causei the complete compression ,oi'fthe material, the

resistance of the material to said complete compression stopping the fluidpressure flow to the secondary cylinder and directing it to .cause the die to move to strip the briquette formed from the material while theplunger is holding the briquette against the frame part, and other means for directing the fluid under pressure to cause the parts to move to their initial positions and to releasethe completed briquette.

5. A briquetting machine, comprising a frame, a hopper for holding loose material,

a die member adjacent the hopper, a plunger extending into the hopper in alinement with the die, a primary cylinder having a piston for moving the plunger to force material from the hopper into the die and against a frame part and to initially compress said material. to a predetermined extent, a secondary cylinder of larger diameter having a plston for moving the plunger with greater-pressure for completing the. compression of the material, a pump and a fluid holding tank positioned to supply fluid under pressure to the 1 primary cylinder and at the same time permit fluid to quickly and freely flow from the tank to the secondary cylinder during the initial compressing ofthe material, a valve controlled by the resistance of the material being compressed for directing fluid under.

pressure to the secondary cylinder to cause the complete compression of the material,

the resistance of the material] to said complete compression stopping the fluid pressure flow to the secondary cylinder and di-' recting it to cause therdie to move tostrip the briquette formedfrom the material while" the plunger is holding the briquette against" the frame part, and electrical means actuat ed by a movable part'of the machine for directing the fluid under pressure to cause the parts to move to their initial positions and to release the completed briquette.

6. A briquetting machine, comprising a frame, a hopper for holding loose material,

a die member adjacent the hopper, a plunger extending into the hopper in alinementwith 1 the die, a primary cylinder having a piston for moving the plunger to force 'material from the hopper into the die and against a terial to a predetermined' extent, a secondary riahia pump and'a' fluid holding tank po s'i tioned to supply fiuid under; pressure to the frame part and to initiall y compress said ma 9 cylinder oflarger, diameter having' a piston, formoving the plunger with greater pressurei for completingthecompression of the mateprimary cylinder and at the same tiine' l per- .7

mitfiuid to quickly and freely .flow from the tank; to the secondarycylinder during the initialcompressing of the material, avalve controlled by the, resistance r of the material the; complete compression of the material,

the resistance; of I the material, to said; com plete compression stopping the fluid pressure, flow to the secondary cylinder and directing being compressed for directing fluid under, pressure to the secondary cylmde'rto cause itto cause thehopper and die to move rear- Wardly to strip the briquettefrom the die while the plunger holding the briquette' aga nst the frame part, electrical means actuated byl the movement of the'hopperiand die for directing the fluid under pressure to cause the "plunger to move rearwardly to its initial fposition to release the completed briquette and :to, also cause the-fluid under pressure tdjmoye: the hopper and die "forwardly totheir initial positions, said forward move- I ment actuating the electrical means to cause the parts to again start their cycle of move 7 A briquetting machine, comprising a frame having spaced guides, a hopper slid ably mounted on' the guides, a die member. carried bythe hopper, a primary and a sec-Q ondary cylinder 'position'ed in endwise rela can on the frame and to whichthe'guides are a connected, aprim'ary piston withinfthe primary cylinder, a secondary piston Within the secondary cylinder,".a plunger connected to said pistons and extending into said hopper to force. material ,therefromjintothe'die, a I 7 frame partagainst which the material in the die is forced, stripperand stripper return cylinders 'havingconnected together pistons:

to whichithehopperiis connecteda storage tank positioned above-the secondary cylinder and having a valve casinge'xtendingupward-y:

lie

lytherein from the secondarycylinder,said valve casing having ducts and ports leading from the tank to the cylinder to permitthe free ofgfiuid from thetankto the cy'l -l inder, a 'fluid 1 pressure pump, id ucts conn fie ns t er p td th t and the cylinders and the tank valveicasingypressure respon sive. valves controllingthe flow of pressure fluid throughsaidducts, and a main valve controlled .bythe movement of the die for controlling the movement ofthe othervalves; I f I vA: briop letting machine, comprising a frame having spaced a hopper slid-5' lyem nt d the, :eaid eg d m mb carrie'd byfthe hopper,,a .primary and a'seconda ry cylinder positioned i BDC WiSejQreIai tion on the frame and to which'the guides die is forced, said frame part havin areconnected, a primary piston within the r j primary cylinder,fa secondarypiston within the secondary cylinder,'a plunger connected to said pistonsa-nd extending'into said hopper to force material therefrom into the die, a frame part against which the material in the d a yielding member for forcing the completed bri (other valves.

quette away from the frame part stripper and stripper return cylinders having connectedtogether pistons'to which the hopper is connected, a storage tank positioned above the secondary, cylinder and having a valve Y casing extending upwardly therein from the secondary cylinder,'said valve casing having ducts and ports leading from the tankto the cylinder to permit the free flow of fluid from the tank to the cylinder, a fluid pressure pump, ducts connecting the pump to the tank and the cylinders and the tank valve casing,

pressure responsive valves controlling the flow of pressure fluid through said ducts, and a main valve controlled by the movementof' the die for controlling the movement of the 9. A briquettin-g machine,comprising a die the fiow'ofthe fluid hem said storagetank to the secondary cylinder,;stripper andstripper return pistons and'-'cylinders,ducts for supplying the fluid to all of said cylinders,

andmeans controlling' the application of p p pressure to the fluid, 2

ture's; V Y J i Q ERLE J; BYERLEIN'.

FRED G F In testimony whereof we aflixour signa -i member, a hopper member moving therewith for holding loose material, a plunger member, a primary cylinder and piston for moving the plunger to force material from the hopper I member into the die member and partly compressing the material in said die member, a secondary cylinder and piston for further moving the plunger to complete the compression of the material, a storage tank positioned above the secondary cylinder for supplyinga fluid to the secondary cylinder freely'by gravity for a portion of the stroke of the secondary piston and for supplying the fluid under pressure for the completion of the stroke ofthe said secondary piston, a pump for applying power to the fluid medium, stripper and stripper return pistons and cylinders,-ducts for supplying the fluid to all-of said cylinders, and means controlling the ap- 'plication ofthe pump pressure to the fluid.

10. A briquetting machine, comprising a die member,a hopper membermoving therewith for holding loose material a plum er member,.a primary cylinderand piston %or moving the plunger toforcematerial from I the hopper member into the die member and partly compressing the material in said die member, a secondary cylinder and piston for further moving the plunger to complete the compression of the material, a storage tank" positioned above the secondary cylinder for.

- I 60, supplying-afluid to the secondary cylinder 

